1. Field of the Invention
This invention relates to electric and hydraulic vehicles and more particularly to a dual motor vehicle having an improved electronic steering and control assembly.
2. Description of the Related Art
Personal mobility vehicles may be characterized as either scooter type personal mobility vehicles or powerchair type personal mobility vehicles. Each of the scooter type personal mobility vehicles and the powerchair type personal mobility vehicles have certain advantages and disadvantages.
A scooter type personal mobility vehicle typically comprises an elongated frame having front single or plural steering wheels and plural rear drive wheels. The front single or plural steering wheels are pivotably mounted on the front portion of the elongated frame. A handlebar is provided for pivoting the front single or plural steering wheels for steering the personal mobility vehicle.
The plural rear wheels are mounted on independent axially aligned shafts driven by a single electric motor though a differential gearbox. The electric motor is controlled by a electronic controller and a speed, braking and forward/reverse engager located on the handlebar of the scooter. The scooter type personal mobility vehicle is well suited for unconfined areas such as outside use due to the superior ride of the elongated wheelbase of the scooter. The elongated wheelbase provides more stability and a better ride for the scooter type personal mobility vehicle.
A powerchair type personal mobility vehicle typically comprises a short frame having plural drive wheels and plural caster wheels. The plural drive wheels may be located in the front, center or the rear drive of the powerchair type personal mobility vehicle. Plural caster wheels complement the plural drive wheels of the powerchair type personal mobility vehicle.
The plural drive wheels are independently driven by plural electric motors. Each of the plural electric motors is independently controlled by a dual motor controller for independently driving the plural electric motors.
Typically, a joystick is mounted on an armrest of a powerchair type personal mobility vehicle for controlling the first and second drive motors. The joystick operates both the steering as well as the speed, braking and forward/reverse movements of the powerchair. The steering of the powerchair is accomplished by a differential in speed between the plural independently driven electric motors including the reverse rotation of one of the electric motors relative to the other of the electric motors to turn the powerchair. The powerchair type personal mobility vehicle is well suited for confined areas such as inside use due to the short frame and the superior turning radius of the plural independently driven electric motors. The short wheelbase and the ability to reverse one motor relative to the other motor provides a reduced turning radius for the personal mobility vehicle for negotiating smaller confined spaces indoors.
The basic commands for driving both types of personal mobility vehicles are: go forward or backward; turn left or turn right; go faster or slower; and stop. Unfortunately, the manipulation of a joystick of a powerchair to control the multiple functions of steering, propulsion and braking is not intuitive or obvious to a new user or a cognitively impaired user.
Many new users find it difficult to operate a powerchair type personal mobility vehicle due to the lack of prior experience using a single interface joystick device that combines steering, turning, speed, braking and forward/reverse controls. In contrast, the manipulation of the handlebar in a scooter type personal mobility vehicle with independent drive controls is intuitively obvious to a new user due to past experience operating tricycles, bicycles and automobiles with independent steering and drive controls.
Therefore, it is an object of the invention to provide an electronic steering assembly with independent drive controls for a dual motor vehicle that separates the physical movements necessary to drive a dual motor vehicle so it is intuitively obvious to a new user or a cognitively impaired user.
Another object of the invention is to provide an electronic steering assembly with independent drive controls for a dual motor vehicle that replaces the conventional joystick in a powerchair type personal mobility vehicle.
Another object of the invention is to provide an electronic steering assembly with independent drive controls for a dual motor vehicle that is applicable to any type of electric or hydraulic vehicle having plural drive wheels independently driven by plural electric motors.
Another object of the invention is to provide an electonic steering assembly with independent drive controls for a dual motor vehicle that is applicable to either a powerchair type personal mobility vehicle or a scooter type personal mobility vehicle.
Another object of the invention is to provide an electronic steering assembly with independent drive controls for a dual motor vehicle that is applicable to either a powerchair type personal mobility vehicle or a scooter type personal mobility vehicle that may be operated by an attendant controlling the dual motor vehicle while walking behind the dual motor vehicle with an occupant therein.
Another object of the invention is to provide an electronic steering assembly with independent drive controls for a dual motor vehicle that is applicable to a platform type vehicle that may be operated by a person when standing on the platform.
Another object of the invention is to provide a steering assembly for an electric vehicle that may replace a joystick on existing powerchair type personal mobility vehicles.
The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed as being merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be obtained by modifying the invention within the scope of the invention. Accordingly other objects in a full understanding of the invention may be had by referring to the summary of the invention, the detailed description describing the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.